Infectious endocarditis

Infectious endocarditis. It is a serious disease, with a varied clinical presentation, which is often confused with other heart conditions and other apparatus and systems; hence its great medical importance, because if it is not recognized and treated properly, it can be fatal.


[ hide ]

  • 1 Definition
  • 2 Classification
  • 3 Clinical manifestations and Diagnosis
  • 4 Duke criteria modified
  • 5 Heart disease at risk of infective endocarditis
  • 6 Procedures requiring prophylaxis
  • 7 Indications for surgical treatment
  • 8 Complications
  • 9 Indicators of poor prognosis
  • 10 Sources
  • 11 External links


Anatomoclinical entity characterized by microbial infection of the parietal valvular endothelium or both caused by different species of microorganisms whose colonies are deposited below the fibrin surface.


traditional classification



  • It manifests with marked toxicity.
  • Withering course
  • Rapid destruction of endocavitary structures.
  • It generally affects healthy hearts.
  • It causes septic metastases.
  • Causal Germ: Streptococcus viridans.
  • If not treated, it is fatal in a few days or weeks.

II- Subacute


  • General nonspecific manifestations of low toxicity.
  • It occurs insidiously.
  • It is located in previously damaged hearts.
  • It does not usually produce septic metastases.
  • Causal Germ: Staphylococo aureus.
  • Even without treatment the patient can live up to a year.

Current ranking

  1. Infective native valve endocarditis (EIVN)

II.Infectious prosthetic valve endocarditis (EIVP)

III.Infectious endocarditis in parenteral drug addicts (EIADVP)

Both classifications can be merged example:

  • Native mitral valve streptococcal subacute infectious endocarditis.
  • Staphylococcal acute infectious endocarditis of the prosthetic aortic valve.

Clinical manifestations and Diagnosis

IE should be suspected in the following cases:

  • New regurgitant heart murmur.
  • Embolic events of unknown origin.
  • Sepsis of unknown origin (especially if associated with an organism causing IE)
  • Fever

IE should be suspected if fever is associated with:

  • Intracardiac prosthetic material.
  • EI Background.
  • Valvular disease or previous congenital heart disease .
  • Other predispositions to IE (eg, immunodeficient status).
  • Predisposition and recent intervention with associated bacteremia.
  • Evidence of congestive heart failure.
  • New driving disorder.
  • Positive blood culture with a typical organism causing IE or positive serology for chronic Q fever (microbiological results may precede cardiac manifestations).
  • Vascular or immune phenomenon: embolic event, Roth spots, splinter hemorrhages, Janeway lesions, Osler’s nodules.
  • Focal or non-specific neurological symptoms and signs.
  • Evidence of pulmonary embolism / infiltration (right IE).
  • Peripheral abscesses (renal, splenic , cerebral, vertebral) of unknown cause.

Modified Duke criteria

Duke’s criteria modified for the diagnosis of infective endocarditis.

Major criteria

Positive blood cultures for IE:

  • Typical microorganisms that match the IE of two independent blood cultures:

Streptococcus viridans, S. bovis, HACEK group, Staphylococcus aureus, or community-acquired Enterococci in the absence of a primary focus

  • Microorganisms that match IE with persistently positive blood cultures:

At least two possible positive cultures of blood samples taken at 12 h intervals or Three or most of more than four independent blood cultures (with the first and last samples taken at intervals of at least 1 h)

  • Single positive blood culture for Coxiella burnetii or phase I IgG antibody 1: 800

Evidence of endocardial involvement

  • Positive echocardiography for IE.
  • Vegetation; abscess; new partial dehiscence of prosthetic valve.
  • New valve regurgitation.

Minor criteria

  • Predisposition: predisposing heart disease, use of drugs by injection.
  • Fever: temperature> 38 ° C.
  • Vascular phenomenon: severe arterial embolus, septic pulmonary infarction, aneurysm, intracranial hemorrhages, conjunctival hemorrhages, Janeway lesions.
  • Immune phenomenon: glomerulonephritis, Osler’s nodules, Roth’s spots, rheumatoid factor.
  • Microbiological evidence: positive blood culture that does not meet an important criterion or serological evidence of active infection.
  • with an organism that fits the IE.

The diagnosis of is definitive in the presence of:

  • 2 major criteria, and / or
  • 1 major criterion and 3 minor importance, and / or
  • 5 minor criteria.

The diagnosis of IE is possible in the presence of:

  • 1 major criterion and 1 minor importance, and / or
  • 3 minor criteria.

Heart disease at risk of infective endocarditis

There are heart diseases at risk of IE for which prophylaxis is recommended when performing a high-risk procedure:

High risk

  • Valve prostheses (including bioprostheses and homografts).
  • Previous infectious endocarditis.
  • Cyanotic congenital heart disease.
  • Patent ductus arteriosus.
  • Aortic insufficiency .
  • Aortic stenosis .
  • Mitral regurgitation .
  • Double mitral injury.
  • Ventricular septal defect.
  • Aortic coarctation .
  • Intracardiac lesions operated with residual hemodynamic abnormalities or prostheses.
  • Pulmonary systemic short circuits with surgical correction.

Moderate risk

  • Pure mitral stenosis.
  • Tricuspid valve disease.
  • Pulmonary stenosis.
  • Hypertrophic cardiomyopathy.
  • Mitral prolapse with valve insufficiency and / or redundant leaflets.
  • Bicuspid aorta with slight hemodynamic abnormalities.
  • Aortic sclerosis with slight hemodynamic abnormalities.
  • Calcific degenerative valvular lesions in the elderly.
  • Intracardiac lesions operated without hemodynamic abnormalities in the first 6 months after the intervention.

Low risk

  • Ventricular septal defect (CIA) ostium secundum.
  • CIA and ductus repair after 6 months and without residual injuries.
  • Coronary surgery.
  • Mitral prolapse without valve failure.
  • Functional puffs.
  • Kawasaki disease without valve dysfunction.
  • Previous rheumatic fever without valve dysfunction.
  • Pacemakers (endocavitary and epicardial) and implanted defibrillators.
  • Mild Doppler valve insufficiency without structural abnormality.
  • Atherosclerotic plates.

Procedures requiring prophylaxis

The procedures for which prophylaxis is recommended in risk patients are:

  • Dental interventions that cause gingival or mucosal bleeding including dental cleaning and tartar removal.
  • Tonsillectomy and adenoidectomy .
  • Surgery of the gastrointestinal muscle or the upper part of the respiratory system.
  • Bronchoscopy with a rigid bronchoscope.
  • Sclerotherapy for esophageal varices.
  • Esophageal dilation.
  • Retrograde endoscopic cholangiography with biliary obstruction.
  • Gallbladder surgery.
  • Cystoscopy, urethral dilation.
  • Urethral catheterization if there is a urinary infection.
  • Surgery of the urinary system including the prostate.
  • Incision and drainage of the affected tissue.

Indications for surgical treatment

The main indications for surgery in patients with infective endocarditis are:

  • Moderate to severe congestive heart failure.
  • Unstable prosthesis.
  • Persistent and uncontrollable infection despite correct antimicrobial treatment.
  • Confirmation of abscesses, pseudoaneurysms, abnormal communications, such as fistulas or rupture of one or more valves; conduction disorders, myocarditis, or other findings indicating local spread (locally uncontrolled infection).
  • Recurrence of prosthetic valve endocarditis after correct treatment.
  • Repeat embolisms with persistent images of large, mobile vegetation.
  • Involvement of microorganisms that do not respond normally to antimicrobial therapy.


  • Congestive heart failure.
  • Thromboembolism at different levels.
  • Arrhythmias
  • Acute kidney failure.
  • Severe valve damage.
  • Brain abscess.
  • Rheumatic complications.
  • Myocarditis and / or pericarditis.

Poor prognosis indicators

Patient characteristics

  • Advanced age.
  • Infectious endocarditis on prosthetic valve.
  • Insulin-dependent diabetes mellitus.
  • Comorbidity (cardiovascular, kidney disease

or previous lung).

  • Presence of complications of infectious endocarditis.
  • Heart failure.
  • Kidney failure .
  • Septic shock.
  • Perianular complications.


  • Staphylococcus aureus.
  • Gram-negative rods.

Echocardiographic results

  • Perianular complications.
  • Regurgitation of the severe left valve.
  • Lower left ventricular ejection fraction.
  • Pulmonary hypertension.
  • Large vegetation.
  • Severe prosthetic dysfunction.
  • Premature closure of the mitral valve and other signs of elevated diastolic pressure.

Leave a Comment